This is one of those questions that result in few, if any, identical answers. Ask a bunch of people why they drive the car they drive, and more than one person might cite fuel efficiency, or its ability to accelerate from 0 to 60 in nothing flat, or its handling on curves, or its seating capacity and cargo space, or the prestige associated with it, or one of the other central considerations associated with one's choice of automobile.
In explaining why they ride the bikes they ride, people tend to speak in more intimate, complex and affectionate terms extolling virtues like utility, comfort, responsiveness, fit, versatility and durability in ways that invoke a sense of enthusiasm and fun. Why do you ride the bike you ride? I started asking the question this year, and have yet to hear the same answer repeated twice. The answers are as distinctive as the make and model each person chooses as unique as the individual riding it. Here are some examples.